In a galaxy as old and vast as the Milky Way, the probability of two civilisations stumbling upon one another by briefly screaming in random directions… is not great.
I love science videos like this on YouTube. Also, the above excerpt feels very Douglas Adams in nature. Like my favourite description of all time, from when the Vogons first appear around the Earth, in Hitchhikers Guide to the Galaxy:
The ships hung in the sky in much the same way that bricks don’t.
Documenteering 